Question

Find the number of terms in the expression obtained by adding the following expressions:
$9x^2-2\mathrm{yz}\mathrm{and}2y+x^2.$

Answer 1

$(9x^2-2\mathrm{yz})+(2y+x^2)=(9+1)x^2-2\mathrm{yz}+2y=10x^2-2\mathrm{yz}+2y$
So, The number of terms in the final expression is 3, thus, it is a trinomial.